21142758 has 32 divisors (see below), whose sum is σ = 52045056. Its totient is φ = 5575968.

The previous prime is 21142753. The next prime is 21142777. The reversal of 21142758 is 85724112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21142753) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18816 + ... + 19907.

It is an arithmetic number, because the mean of its divisors is an integer number (1626408).

Almost surely, 2^21142758 is an apocalyptic number.

21142758 is an abundant number, since it is smaller than the sum of its proper divisors (30902298).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21142758 is a wasteful number, since it uses less digits than its factorization.

21142758 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38748.

The product of its digits is 4480, while the sum is 30.

The square root of 21142758 is about 4598.1254876308. The cubic root of 21142758 is about 276.5161785423.

The spelling of 21142758 in words is "twenty-one million, one hundred forty-two thousand, seven hundred fifty-eight".